The use of various attachment lenses in conjunction with a still camera to achieve special effects has been conventionally known. However, due to the popularization of disposable or reusable cameras (i.e., lens-attached film) and the growing trend for portrait photo sticker machines, the taking of photos in recent years has been broadly penetrating onto the daily lives of general people. Additionally, photography is becoming not just the photographing of a photographic object as it actually is, but activities such as pen-writing on the photo and digitalizing the photo for further processing as well as other forms of enjoyment with photos are being commonly performed.
With this type of photographic development history, there is a growing demand to take photos and to perform special effects easily, even by persons unskilled in photography. An example of this type of special effect is photographing a heavy person so as to appear thin, or vice-versa.
As examples of prior art anamorphic attachment lenses which have the ability to achieve the special effect described above, the attachment lenses disclosed in Japanese Laid-Open Patent Application 57-8514 and Japanese Laid-Open Patent Application 7-333497 can be given. Both of these attachment lenses have the ability to form an image where the magnification in the vertical direction and the horizontal direction are mutually different with an angular magnification of 0.9 to 1.3, and each attachment lens includes two cylindrical lens elements. The lens material is assumed to be glass. The complexity and size of these attachment lenses have kept these lenses from widespread use by the general public.